The present disclosure is directed to a catalyst composition used in the production of aromatic carbonates, and in particular to a catalyst composition which comprises an activating solvent. In one embodiment, the catalyst composition comprises combination of at least two activating solvents, a first activating solvent chosen for its coordinative properties, and a second activating solvent chosen for its dielectric constant properties. In other embodiments, the present disclosure also pertains to methods for producing aromatic carbonates using the catalyst compositions disclosed herein.
A useful method for the production of aromatic carbonates includes the oxidative carbonylation of aromatic hydroxy compounds, with carbon monoxide and oxygen, which is typically catalyzed by a catalyst composition comprising a Group 8, 9 or 10 metal catalyst, a salt source, optionally various metal co-catalyst sources, and optionally a base source. In some instances, a significant improvement to catalyst performance, in terms of both of activity and selectivity, can be achieved when the catalyst composition further includes an activating solvent. The use of certain activating solvents are known to aid in the dissolution and dissociation of certain components of a carbonylation catalyst composition in a typical carbonylation reaction mixture. For instance, the solubility and dissociation of alkali halide and alkaline earth halide salt sources in typical carbonylation reaction mixtures comprising aromatic hydroxy compounds are known to be significantly improved when certain types of activating solvents are present in the catalyst composition.